<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script>
        //字符串检索
        var rag = /hello/;
        console.log(rag.exec('hello'));
        //exec()方法检索字符串中的指定值。返回被找到的值，没有发现匹配值则返回null
    </script>
</head>
<body>

</body>
</html>